CVE-2023-26044
ReactPHP's HTTP server continues parsing unused multipart parts after reaching limits
react/http is an event-driven, streaming HTTP client and server implementation for ReactPHP. Previous versions of ReactPHP's HTTP server component contain a potential DoS vulnerability that can cause high CPU load when processing large HTTP request bodies. This vulnerability has little to no impact on the default configuration, but can be exploited when explicitly using the RequestBodyBufferMiddleware with very large settings. This might lead to consuming large amounts of CPU time for processing requests and significantly delay or slow down the processing of legitimate user requests. This issue has been addressed in release 1.9.0. Users are advised to upgrade. Users unable to upgrade may keep the request body limited using RequestBodyBufferMiddleware with a sensible value which should mitigate the issue. An infrastructure or DevOps workaround could be to place a reverse proxy in front of the ReactPHP HTTP server to filter out any excessive HTTP request bodies.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
5.3
ReactPHP's HTTP server continues parsing unused multipart parts after reaching limits
react/http is an event-driven, streaming HTTP client and server implementation for ReactPHP. Previous versions of ReactPHP's HTTP server component contain a potential DoS vulnerability that can cause high CPU load when processing large HTTP request bodies. This vulnerability has little to no impact on the default configuration, but can be exploited when explicitly using the RequestBodyBufferMiddleware with very large settings. This might lead to consuming large amounts of CPU time for processing requests and significantly delay or slow down the processing of legitimate user requests. This issue has been addressed in release 1.9.0. Users are advised to upgrade. Users unable to upgrade may keep the request body limited using RequestBodyBufferMiddleware with a sensible value which should mitigate the issue. An infrastructure or DevOps workaround could be to place a reverse proxy in front of the ReactPHP HTTP server to filter out any excessive HTTP request bodies.
- Record
CVE-2023-26044- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-400
- Updated
- 2026-11-02
EUVDEUVD-2023-1509
5.3
react/http is an event-driven, streaming HTTP client and server implementation for ReactPHP. Previous versions of ReactPHP's HTTP server component contain a potential DoS vulnerability that can cause high CPU load when processing large HTTP request bodies. This vulnerability has little to no impact on the default configuration, but can be exploited when explicitly using the RequestBodyBufferMiddleware with very large settings. This might lead to consuming large amounts of CPU time for processing requests and significantly delay or slow down the processing of legitimate user requests. This issue has been addressed in release 1.9.0. Users are advised to upgrade. Users unable to upgrade may keep the request body limited using RequestBodyBufferMiddleware with a sensible value which should mitigate the issue. An infrastructure or DevOps workaround could be to place a reverse proxy in front of the ReactPHP HTTP server to filter out any excessive HTTP request bodies.
- Record
EUVD-2023-1509- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-95x4-j7vc-h8mf
5.3
ReactPHP's HTTP server continues parsing unused multipart parts after reaching input field and file upload limits
Summary
Previous versions of ReactPHP's HTTP server component contain a potential DoS vulnerability that can cause high CPU load when processing large HTTP request bodies. This vulnerability has little to no impact on the default configuration, but can be exploited when explicitly using the RequestBodyBufferMiddleware with very large settings. This might lead to consuming large amounts of CPU time for processing requests and significantly delay or slow down the processing of legitimate user requests.
Patches
The supplied patch resolves this vulnerability for ReactPHP.
Workarounds
-
Keeping the request body limit using
RequestBodyBufferMiddlewaresensible will mitigate it. -
Infrastructure or DevOps can place a reverse proxy in front of the ReactPHP HTTP server to filter out any excessive HTTP request bodies.
References
A similar vulnerability was discovered in PHP recently, see also PHP's security advisory (CVE-2023-0662). The fix is based on the PHP-FPM fix.
- Record
GHSA-95x4-j7vc-h8mf- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-400
- Updated
- 2026-11-02
NVD
5.3
react/http is an event-driven, streaming HTTP client and server implementation for ReactPHP. Previous versions of ReactPHP's HTTP server component contain a potential DoS vulnerability that can cause high CPU load when processing large HTTP request bodies. This vulnerability has little to no impact on the default configuration, but can be exploited when explicitly using the RequestBodyBufferMiddleware with very large settings. This might lead to consuming large amounts of CPU time for processing requests and significantly delay or slow down the processing of legitimate user requests. This issue has been addressed in release 1.9.0. Users are advised to upgrade. Users unable to upgrade may keep the request body limited using RequestBodyBufferMiddleware with a sensible value which should mitigate the issue. An infrastructure or DevOps workaround could be to place a reverse proxy in front of the ReactPHP HTTP server to filter out any excessive HTTP request bodies.
- Record
CVE-2023-26044- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-400
- Updated
- 2026-11-02
OSV
5.3
ReactPHP's HTTP server continues parsing unused multipart parts after reaching limits
react/http is an event-driven, streaming HTTP client and server implementation for ReactPHP. Previous versions of ReactPHP's HTTP server component contain a potential DoS vulnerability that can cause high CPU load when processing large HTTP request bodies. This vulnerability has little to no impact on the default configuration, but can be exploited when explicitly using the RequestBodyBufferMiddleware with very large settings. This might lead to consuming large amounts of CPU time for processing requests and significantly delay or slow down the processing of legitimate user requests. This issue has been addressed in release 1.9.0. Users are advised to upgrade. Users unable to upgrade may keep the request body limited using RequestBodyBufferMiddleware with a sensible value which should mitigate the issue. An infrastructure or DevOps workaround could be to place a reverse proxy in front of the ReactPHP HTTP server to filter out any excessive HTTP request bodies.
- Record
CVE-2023-26044- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-400
- Updated
- 2026-11-02
OSVGHSA-95x4-j7vc-h8mf
5.3
ReactPHP's HTTP server continues parsing unused multipart parts after reaching input field and file upload limits
Summary
Previous versions of ReactPHP's HTTP server component contain a potential DoS vulnerability that can cause high CPU load when processing large HTTP request bodies. This vulnerability has little to no impact on the default configuration, but can be exploited when explicitly using the RequestBodyBufferMiddleware with very large settings. This might lead to consuming large amounts of CPU time for processing requests and significantly delay or slow down the processing of legitimate user requests.
Patches
The supplied patch resolves this vulnerability for ReactPHP.
Workarounds
-
Keeping the request body limit using
RequestBodyBufferMiddlewaresensible will mitigate it. -
Infrastructure or DevOps can place a reverse proxy in front of the ReactPHP HTTP server to filter out any excessive HTTP request bodies.
References
A similar vulnerability was discovered in PHP recently, see also PHP's security advisory (CVE-2023-0662). The fix is based on the PHP-FPM fix.
- Record
GHSA-95x4-j7vc-h8mf- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Weakness
- CWE-400
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2023-26044
5.3
react/http is an event-driven, streaming HTTP client and server implementation for ReactPHP. Previous versions of ReactPHP's HTTP server component contain a potential DoS vulnerability that can cause high CPU load when processing large HTTP request bodies. This vulnerability has little to no impact on the default configuration, but can be exploited when explicitly using the RequestBodyBufferMiddleware with very large settings. This might lead to consuming large amounts of CPU time for processing requests and significantly delay or slow down the processing of legitimate user requests. This issue has been addressed in release 1.9.0. Users are advised to upgrade. Users unable to upgrade may keep the request body limited using RequestBodyBufferMiddleware with a sensible value which should mitigate the issue. An infrastructure or DevOps workaround could be to place a reverse proxy in front of the ReactPHP HTTP server to filter out any excessive HTTP request bodies.
- Record
UBUNTU-CVE-2023-26044- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
react/httpPackagist |
0.8.0 up to 1.9.0 | 1.9.0 |
react/httpPackagist |
0.8.0 up to 1.9.0, plus listed versions v0.8.0v0.8.1v0.8.2v0.8.3v0.8.4 Show 12 moreShow lessv0.8.5v0.8.6v0.8.7v1.0.0v1.1.0v1.2.0v1.3.0v1.4.0v1.5.0v1.6.0v1.7.0v1.8.0 |
1.9.0 |
php-react-httpUbuntu:20.04:LTS |
All versions, plus listed versions 0.8.3-3 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-26044 is a medium vulnerability (CVSS 5.3) in Reactphp Http, published May 17, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.68%, the 52nd percentile. Fixed in react/http 1.9.0.
References
github.com/reactphp/http/security/advisories/GHSA-95x4-j7vc-h8mf
github.com/reactphp/http/commit/9681f764b80c45ebfb5fe2ea7da5bd3babfcdcfd
github.com/php/php-src/security/advisories/GHSA-54hq-v5wp-fqgv
github.com/php/php-src/commit/716de0cff539f46294ef70fe75d548cd66766370
github.com/reactphp/http/releases/tag/v1.9.0
nvd.nist.gov/vuln/detail/CVE-2023-26044
Show 7 moreShow less
github.com/FriendsOfPHP/security-advisories/blob/master/react/http/CVE-2023-26044.yaml
github.com/advisories/GHSA-95x4-j7vc-h8mf
github.com/CVEProject/cvelistV5/tree/main/cves/2023/26xxx/CVE-2023-26044.json
github.com/reactphp/http
ubuntu.com/security/CVE-2023-26044
github.com/reactphp/http/commit/b3594f7936b92f9fc2d5f9e84dc01bdb95a72167
cve.org/CVERecord?id=CVE-2023-26044